Process and apparatus for orienting yarn



Nov. 30, 1965 E. v. MARTIN PROCESS AND APPARATUS FOR ORIENTING YARN Filed NOV. 2, 1964 MOTOR GODE T TENSION ROLLS I m L mmm 7; I T s L m m M n E E H M LUM E H 7 PA i H T m Ms M m F "5 m 1 1 /T\ W \\\\\\\E\\ p D|| m Trff fiw o LIQUID n i 5 MM m u aw m 0 M /O o R I W /T N L 3 v] ,T m L M MA E00 1 o r m r M-J MW W N 9 N iZw R I! m v\w MW GA 2 m Us wo M w A w R Q m n In "Pm/MW 7/)!1/ 7/ c a United States Patent 3,221,088 PROCESS AND APPARATUS FOR ORIENTING YARN This application is a continuation-in-part of my application Serial No. 86,511, filed February 1, 1961, now abandoned. This invention relates to the manufacture of oriented melt spun polymer filament yarns. More particularly this invention concerns process and apparatus for orientating polyester filament products, as highly elastomeric yarns, in a more simple and satisfactory manner.

It is well-known in the textile industry that many polymeric filaments as extruded from their filament-forming composition, such as by melt spinning or the like procedure, do not have suitable or the desired properties as thus formed. Therefore, it is already customary to subject such filaments and yarn to various after treatments such as stretching, heat treatment and similar treatments for orienting and otherwise altering the properties of the resultant yarn product. In accordance with prior methods in some instances the filaments as first formed are wound into packages and the yarn is then unwound from the packages through stretching and heat setting. In other instances the yarn that is produced has been passed over and around temperature-controlled rolls operating at differential speeds to produce stretching or other changes in the filaments. A number of other methods and apparatus involving the use of snubbing pins, heaters and the like have been proposed for treating filaments and yarn products.

In the manufacture of certain polyester yarn products as of a type which may tend to be somewhat tacky or gummy as melt spun but which filaments in their final form exhibit high elasticity, it has not been entirely satisfactory to utilize prior art methods of after treatment. That is, in the prior art methods, there has been a tendency for the filaments to adhere to one another or to stick to the rolls or present other difliculties.

Therefore, it is apparent that the development of further methods and apparatus for the after treatment for yarn products, particularly polyester filaments which may tend to stick or coalesce represents a highly desirable result. After extended investigation I have found a method and apparatus which not only is useful for the after treatment of polyester yarns which may tend to adhere together as formed but which may also be used in the after treatment of more conventional polymeric yarns that are relatively firm and non-tacky as produced.

This invention has for one object to provide a new process and apparatus for the after treatment of polymeric filaments and yarns. Another object is to provide process and apparatus particularly useful for the after treatment of certain melt spun polyester filaments which may tend to adhere to one another in a freshly formed state. A particular object is to provide a new process of orienting polymeric yarns in a liquid bath whereby the resistance of the liquid bath to the movement of the filaments thus imparts tension and other effects on the filaments thereby facilitating the orientation of such filaments. Still another object is to provide a liquid bath of the type just referred to whereby through the positioning thereof, temperature control and other factors, the properties of the resultant filaments treated therein may be controlled. Still another object is to provide simple and relatively non-complex apparatus for carrying out the foregoing. Other objects will appear hereinafter.

In the broader aspects of my invention I have found that freshly formed filaments of the type referred to above may be passed through a bath of liquid and drawn from the bath under tension produced by the bath sutficient to accomplish the desired degree of orientation of their molecular structure. The viscosity and/ or pressure of the liquid and the distance and rate of travel of the filaments through the liquid are adjusted 'so that the drag of the liquid on the filaments efficiently provides at least the greater part of the tension required for the orientation. Since the temperature at which the orientation drafting is carried out may be important as respects yarns of certain compositions, the temperature of the liquid bath of the present invention may be readily adjusted and controlled along with the distance and rate of travel of the yarn being processed to obtain the desired orientation and properties of the yarn.

The degree of quenching or cooling of the freshly produced filaments that occurs before the filaments enter the liquid bath of the present invention can be adjusted from very little to nearly complete cooling by varying the distance from the spinneret to the liquid surface. This distance may be varied from a few inches to several feet. Also the quenching or cooling can be controlled by varying the temperature and/or the rate of air or other cooling gas around the filaments in the space between the spinneret and the surface of the liquid.

In accordance with the present invention the filaments of a multi-filament coalescing type polyester yarn are either quite well-quenched before they enter the liquid bath or they are kept separated from each other until they become immersed in the liquid which can also serve to quench the filaments. Otherwise the filaments may tend to coalesce and to produce an unsatisfactory product.

For a further understanding of my invention, reference is made to the attached drawing forming a part of the present application.

FIGURE 1 is a semidiagrammatic side elevation view illustrating an over-all setup of an apparatus for carrying out my invention.

FIGURE 2 likewise is a semidiagrammatic side elevation view of a modified arrangement for practicing the process of the present invention.

FIGURE 3 also is a semidiagrammatic side elevation View of another arrangement of apparatus for practicing the present invention.

Referring to FIGURE 1, 2 represents a melt spinning device into which the polymer may be supplied at 3. The polymer is forced by screw 4 into the spinning head 6. During the passage along the screw, the polymer is heated in a usual manner to a molten fiowable state so that it may be extruded through openings in the head into the filaments 7. Inasmuch as heating the polymer to convert it onto a spinnable condition and the like procedures briefly referred to above may be accomplished by process and apparatus available in the industry, extended description thereof is unnecessary.

The polymer filaments at 7 in a freshly formed condition are kept separated so they will not adhere to one another until they are suitably cooled or quenched. Such cooling may be accomplished by normal air circulation or forced circulation of a cooling material may be supplied against the filaments to cause them to set. This may be accomplished in the distance D which may be from a few inches to several feet which comprises the distance that the spinning head is positioned above the liquid bath of the present invention. The exact distance will be de termined from the polymer composition being spun, the degree of stickiness of the filaments and the like factors. Usually for the filaments formed from the polyester to be described hereinafter in the several examples, the distance would be within the range of inches to feet for normal air cooling. With forced cooling, this distance may be decreased as for example 50%.

The cooled filaments then pass into the liquid bath 8 of the present invention. The hydrostatic head H of this bath may vary depending on the viscosity and pressure of the liquid desired against the filaments. Likewise the length (L) of travel of the filaments in contact with resistance of the liquid bath may vary depending on the tension it is desired to impart to the filaments. As will be noted from the examples which follow, the length L for polyester yarns have usually been from a few inches to several feet.

The temperature of the bath 8 may be controlled by a jacket 10 or other temperature controlling means. For example, as will be referred to hereinafter, when the liquid bath comprises ice water, suitable refrigerant coolant would be maintained in jacket 10. Therefore as may be observed from said FIGURE 1, the filaments are conducted well below the surface of the liquid bath around a guide 5 and are then drawn through the bath some suitable distance L. During this travel through the bath, distance L, resistance is exerted against the filaments so that by withdrawing the filaments through tension rolls 11, the filaments are stretch oriented.

The tension rolls 11 would be rotated at a higher speed than the rate of extrusion of the filaments at 7.

The filaments emerging from the tension rolls 11 may be wound into packages or puddled into a container as indicated at 12. Or as will be described in connection with the examples hereinafter, the filaments may be passed to still additional treatments such as treatment in a chamber with super-heated steam.

Referring now to FIGURE 2, the spinning head 15 may be the same as in FIGURE 1. However, in this alternative arrangement of FIGURE 2, the liquid bath of the present invention rather than being horizontally positioned is vertically positioned in line with the spinneret so that the freshly spun filaments may be discharged downwardly into the orientating bath. In this construction the liquid bath 16 may be of sufiicient depth to provide a path of travel L2 of the desired distance to permit the orientation of the filters. As described in connection with L of FIGURE 1, L2 may be from a few inches to a few feet in length.

The bottom portion of the container 18, as at 19 is provided with a gasketed, lubricated outlet for the yarn. This would permit the withdrawal of the yarn from the container and prevent the escape of any substantial amount of the liquid bath. Such liquid as may escape can be deflected by bafiles 21 and 22 into suitable container (not shown) for return to the liquid bath.

The yarn then is taken up by tension rolls 23 and passes to a collecting container 24 or to other packaging or treatment as already referred to above.

Referring to FIGURE 3, FIGURE 3 is readily understandable from preceding description. The spinning head 25 may be the same, and discharges the filaments into container 26 which holds the liquid bath 27. A guide roll is provided at 28 so that the yarn travel through the bath, in this arrangement, is 2L The rolls 29, 30 and receiver 31 may be comparable to structures already described above.

A further understanding of my invention will be had from a consideration of the following examples which are set forth to illustrate certain preferred embodiments.

Example I A polymer formed by condensing 1 mole of the dibutyl ester of p,p-sulfonyldibenzoic acid and 1.5 moles of dibutyl azelate with 1,4-butanediol was melted in a meltspinning device of conventional type and extruded through a 5-hole spinneret into a column of air 15 feet long. Cn passing around a Godet roll having a surface speed of 1600 feet per minute, the five filaments adhered to each other so tightly that they could not be separated. However, when the filaments were passed around a guide water so that they traveled a few inches through water, as in FIGURE 1, before passing around the Godet roll, they were found not to be adhered togeth- Furthermore, the yarn which had been passed through water was found to have properties which were much more desirable than those which were possessed by the yarn which had been wound without passing through water. This latter yarn could be stretched 200 to 300% before it was oriented sufficiently to have a desirable degree of elastic recovery. However, yarn which had been passed through water could be drawn only 20% at 102 C. This yarn had a tenacity of 1.8 grams per denier, an elongation of and a high degree of elasticity.

Example 11 A polymer of the same composition as in Example I was extruded through a S-hole spinneret at a rate of 3.3 pounds per hour into a column of air about 15 feet long. This yarn thenpassed around a guide immersed in water at room temperature. After traveling in the water a distance of 17 inches, the yarn passed around a Godet roll to a tube winder Where it was wound at a speed of 4300 feet per minute. This yarn as wound was substantially fully drawn and oriented. Its tenacity was 0.9 grams per denier, its elongation was 218%, and its degree of elastic recovery was very high.

Example III The polymer of Example II was extruded at 2.2 pounds per hour under conditions similar to those of Example II except that the distance of travel through the water was ony 2 inches. This yarn weighed 100 denier and was fully drawn as wound. Its tenacity was 1.2 grams per denier, and its elongation was Example IV A polymer formed by condensing dimethyl terephthalate with a mixture of 85 mole percent 1,4-cyclohexanedimethanol and 15 mole percent poly(tetramethyleneglycol) having a molecular weight of approximately 3100 was extruded through a 2-hole jet at a rate of 6.7 pounds per hour. After traveling through air a distance of 12 inches, these filaments were passed under a guide immersed in ice water. After traveling a distance of 3 feet in this water, the filaments were wound separately on a tube winder at a rate of 2480 feet per minute. These monofilaments were then passed at the rate of 75 feet per minute through a chamber 24 inches long containing superheated steam at 200 C., in which they were allowed to relax 20% in length. The monofilaments then were 310 denier, and had a tenacity of 0.4 gram per denier, an elongation of 365%, and a high degree of elastic recovery.

While water, as ice water, has been described as the liquid bath since it is low cost and readily available, other liquids as various hydrocarbons and alcohols may be used. Although a 5-hole spinneret has been referred to, other size, shape and number of openings may be used. As may be observed from the foregoing, my polymers preferably involve three components. Such may comprise two acid constituents and one diol or two diols and one acid constitutent. Such polymers spin at lower temperatures of, for example, within the range of 200 C.- 260 C. to give filaments of lower strengthbut high elongation and elasticity as compared to the known adipic acid-diamine polymers. Hence, my polymers will not withstand high tensions and therefore I used tensions in my process described above of less than .5 gram per denier and frequently below .2 gram per denier.

In using three-component polymers in which two of the components are dibasic acids, I have chosen to limit the molar ratio of the major acid component to the minor acid component to no greater than seven to three. This restriction arises from the fact that yarns made from polymers in which the molar ratio of acids is greater than seven to three either do not have long-range elasticity or are low softening to be useful in commerce. This same reasoning applies to the restriction of the molar of the major diol to the minor diol to no greater than eight to one for those three-component polymers in which two of the three components are diols. It will be observed that one three-component polymer which may be used comprises butanediol, an alkyl ester of dibenzoic acid, and an alkyl ester of a second dibasic acid.

Although the present invention is particularly useful for the after treatment of polymers of the type illustrated in the above examples, especially polymers the filaments of which may tend to adhere when freshly spun, the present invention is useful on filaments from other polymers. For example, the present invention may be utilized in the after treatment of filaments, fibers and yarns produced from the polymer of my co-workers US Patent 2,901,466. The polymers as described in said patent just mentioned but modified with certain aromatic amines in the preparation may be very Well processed by the present invention. Illustrations of some of the modifying amines are dioctyl and diphenyl amines and alphanaphthyl-p-diphenylenediamines.

As apparent from the above examples there has been provided as a result of the after treatment of the present invention yarns which have high elastomeric properties. Therefore, such yarns are useful in areas heretofore dominated by rubber fibers. For example, reference is made to such specific items as self-supporting stockings, foundation garments and the like. Not only do fabrics prepared from yarns of the present invention have the desired elasticity but said fabrics are relatively free from the undesirable properties which accompany fabrics made from rubber fibers.

Although the invention has been described in considerable detail with particular reference to certain preferred embodiments thereof, variations and modifications can be effected Within the spirit and scope of the invention as described hereinabove, and as defined in the appended claims.

I claim:

1. The process of after-treating yarn melt-spun from three-component polymers, the polymers being derived from the group consisting of two acid constitutents reacted with one diol, in which the molar ratio of the major acid component and the minor acid component is no greater than 7 to 3, and two diols reacted with one acid constitutent, in which the molar ratio of the major diol and the minor diol is no greater than 8 to 1, which comprises cooling said filaments as they emerge from the spinnerette by subjecting said filaments to gas cooling in a zone of not more than 15 feet in length and then conducting said filaments into and below the surface of a low temperature-controlled liquid bath of sufificient depth and length wherein the viscosity of the bath exerts tension on the filaments, pulling the filaments through the bath at a speed of not greater than 1600 feet per minute and a ten sion not greater than 0.5 gram per denier but sufiicient to stretch-orient the filaments, and withdrawing to further processing the filaments thus oriented.

2. The process in accordance with claim 1 wherein the yarn is comprised of filaments derived from a polymer made from the three constituents-dimethyl terephthalate, 1,4 cyclohexanedimethanol, and poly(tetramethylene glycol), in which the molar ratio of cyclohexanedimethanol to poly(tetramethylene glycol) is no greater than 8 to 1, and the tension is not greater than 0.2 gram per denier.

3. The process according to claim 1 wherein the yarn is comprised of filaments derived from a polymer made from the three constituents-1,4-butanediol, an alkyl ester of p,p'-sulfonyldibenzoic acid, and an alkyl ester of a second dibasic acid component selected from the group represented by the formula (CH (COOH) in which n is any integer from four to ten, inclusive.

4. The process according to claim 1 wherein the threecomponent polymer yarn is made up of filaments derived from polymer in which the major diol component, as determined on a molar basis, is 1,4-cyclohexanedimethanol.

5. A process in accordance with claim 1 wherein the combined distance through which the filaments travel for gas cooling and in said liquid bath is between approximately a half foot and twenty feet and suflicient to cool the filaments and the liquid is of sufiicient depth to exert substantial tension on the filaments.

6. The process in accordance with claim 1 wherein the filaments after stretch orientation in the liquid bath are further processed by removing from the bath and subjecting the filaments to a stream treatment.

No references cited.

ALEXANDER H. BRODMERKEL, Primary Examiner. 

1. THE PROCESS OF AFTER-TREATING YARN MELT-SPUN FROM THREE-COMPONENT POLYMERS, THE POLYMERS BEING DERIVED FROM THE GROUP CONSISTING OF TWO ACID CONSTITUTENTS REACTED WITH ONE DIOL, IN WHICH THE MOLAR RATIO OF THE MAJOR ACID COMPONENT AND THE MINOR ACID COMPONENT IS NO GREATER THAN 7 TO 3, AND TWO DIOLS REACTED WITH ONE ACID CONSTITUTENT, IN WHICH THE MOLAR RATIO OF THE MAJOR DIOL AND THE MINOR DIOL IS NO GREATER THAN 8 TO 1, WHICH COMPRISES COOLING SAID FILAMENTS AS THEY EMERGE FROM THE SPINNERETTE BY SUBJECTING SAID FILAMENTS TO GAS COOLING IN A ZONE OF NOT MORE THAN 15 FEET IN LENGTH AND THEN CONDUCTING SAID FILAMENTS INTO AND BELOW THE SURFACE OF A LOW TEMPERATURE-CONTROLLED LIQUID BATH OF SUFFICIENT DEPTH AND LENGTH WHEREIN THE VISCOSITY OF THE BATH EXERTS TENSION ON THE FILAMENTS, PULLING THE FILAMENTS THROUGH THE BATH AT A SPEED OF NOT GREATER THAN 1600 FEET PER MINUTE AND A TENSION NOT GREATER THAN 0.5 GRAM PER DENIER BUT SUFFICIENT TO STRETCH-ORIENT THE FILAMENTS, AND WITHDRAWING TO FURTHER PROCESSING THE FILAMENTS THUS ORIENTED. 